Reinforcing layer for proton exchange membrane, proton exchange membrane containing reinforcing layer and preparation method of proton exchange membrane

Abstract

The invention provides a proton exchange membrane which comprises a reinforcing layer and further comprises a dense reinforcing layer and a density reinforcing layer. The reinforcing layer is provided with a catalyst and can be manufactured through electrostatic spinning or 3D printing, due to the low porosity, the compact reinforcing layer can effectively prevent the puncture influence of the anode titanium felt, due to the distribution of the pore structure and the catalyst in the reinforcing layer, the reinforcing layer can reduce hydrogen permeation, and the hydrogen permeation resistance of the anode titanium felt is improved. And a promoting effect is generated on the transportation of protons.

Description

Technical Field

[0001] The present technology relates to applications in the field of electrochemistry, and specifically provides a reinforcing layer for a proton exchange membrane, a proton exchange membrane comprising the same, and a preparation method thereof. Background Art

[0002] Hydrogen energy is an efficient and clean secondary energy source and an important integral part of China's future energy structure. At the same time, as the country with the largest installed capacity of renewable energy in the world, China's utilization of renewable energy for electrolytic hydrogen production and full play of its energy storage attributes will contribute to the formation of a diversified and complementary energy supply system in China.

[0003] Among various hydrogen production technologies, proton exchange membrane water electrolysis (PEMWE) features rapid response, high energy conversion efficiency, high device compactness, wide operating range, etc., and can perfectly adapt to the volatility of renewable energy. For example, proton exchange membrane water electrolysis can be coupled with renewable energy such as wind power and photovoltaic power, enabling the conversion of wind energy or solar energy into hydrogen energy for storage, thereby achieving large-scale, long-term, cross-regional, and cross-seasonal energy storage.

[0004] The core material of proton exchange membrane water electrolysis is the proton exchange membrane (PEM), whose main function is to isolate the anode and cathode electrodes and conduct protons. Due to the characteristics of the electrolyzer, the proton exchange membrane is required to have high selectivity (i.e., high conductivity and low permeability), durability, and low cost.

[0005] However, the durability of the proton exchange membrane is challenged. Specifically, the proton exchange membrane must resist thermal shock, cyclic stress, and radical corrosion during the operation, start-stop process of the water electrolyzer to avoid related failures including thermal failure, mechanical failure, and chemical failure. Among them, the diffusion layer of the anode is mostly made of titanium felt material with relatively high hardness, which is likely to squeeze the proton exchange membrane during operation and cause it to be pierced, further affecting the life of the membrane and the electrolyzer.

[0006] On the other hand, in order to avoid performance deterioration caused by free radicals or hydrogen permeation, prior technologies add catalysts to the membrane. Generally, the catalyst may be coated between layers and then form the proton exchange membrane. Such a process is more complex, and the mechanical strength and conductivity may decrease, and it also affects the durability of the membrane. Summary of the Invention

[0007] To solve the foregoing problems, in a first aspect, the present invention discloses a reinforcing layer for a proton exchange membrane, comprising: a first side; and a second side disposed opposite to the first side; wherein the porosity of the reinforcing layer gradually increases from the first side towards the second side.

[0008] In some embodiments, the reinforcing layer for the proton exchange membrane further includes a dense reinforcing layer disposed on the first side, and the porosity of the dense reinforcing layer is less than or equal to the porosity of the first side.

[0009] In some embodiments, the reinforcing layer for the proton exchange membrane further includes a sparse-dense reinforcing layer disposed on the second side, and the porosity of the sparse-dense reinforcing layer is greater than or equal to the porosity of the second side.

[0010] In some embodiments, the ratio of the porosity of the first side to the porosity of the second side is 1:(1 to 5).

[0011] In some embodiments, the thickness ratio of the dense reinforcing layer to the reinforcing layer is 1:(0.5 to 5), and the ratio of the total thickness of the dense reinforcing layer and the reinforcing layer to the thickness of the sparse-dense reinforcing layer is 1:(2 to 20).

[0012] In some embodiments, the material of the reinforcing layer for the proton exchange membrane is selected from one or more of the following: polyphenylene sulfide (PPS), polyethersulfone (PES), polytetrafluoroethylene (PTFE), polyetheretherketone (PEEK), polysulfone (PSU), polyvinylidene fluoride (PVDF), and sulfonates of any of the above materials.

[0013] In some embodiments, the reinforcing layer for the proton exchange membrane has a catalyst.

[0014] In some embodiments, the catalyst includes a metal catalyst, a radical quencher, or any combination of the above.

[0015] In some embodiments, the metal catalyst is selected from one or more of the following: platinum (Pt), gold (Au), and palladium (Pd).

[0016] In some embodiments, the radical quencher is selected from one or more of the following: cerium dioxide (CeO2), cerium nitrate (CeNO3), and manganese dioxide (MnO2).

[0017] In some embodiments, the mass ratio of the catalyst to the reinforcing layer is 1:(50 to 200).

[0018] In some embodiments, the reinforcing layer for the proton exchange membrane is prepared by electrospinning.

[0019] Second, the present invention provides a method for preparing a reinforcing layer for a proton exchange membrane, including the following steps: P1: Spraying a first dispersion liquid at a first spraying speed that gradually changes to a second spraying speed to form a reinforcing layer, wherein the first dispersion liquid has a framework material, and the first spraying speed is greater than the second spraying speed.

[0020] In some embodiments, the following steps are further included: P2: spraying the first dispersion liquid on one side of the reinforcing layer at the first spraying speed to form a dense reinforcing layer, wherein P2 is arranged before P1.

[0021] In some embodiments, the following steps are further included: P3: spraying the first dispersion liquid on the side of the reinforcing layer relative to the dense reinforcing layer at the second spraying speed to form a sparse-dense reinforcing layer, wherein P3 is arranged after P1.

[0022] In some embodiments, the following steps are further included: P4: simultaneously or alternately with P1, spraying a second dispersion liquid at a third spraying speed to jointly form the reinforcing layer with the first dispersion liquid, wherein the second dispersion liquid has a catalyst.

[0023] In some embodiments, the ratio of the first spraying speed, the second spraying speed, and the third spraying speed is 1:(0.1 to 1):(0.1 to 1).

[0024] In some embodiments, the skeleton material is selected from one or more of the following: polyphenylene sulfide (PPS), polyethersulfone (PES), polytetrafluoroethylene (PTFE), polyetheretherketone (PEEK), polysulfone (PSU), polyvinylidene fluoride (PVDF), and sulfonates of any of the above materials.

[0025] In some embodiments, the catalyst includes a metal catalyst, a radical quencher, or any combination of the above. Among them, the metal catalyst is selected from one or more of the following: platinum (Pt), gold (Au), and palladium (Pd), and the radical quencher is selected from one or more of the following: cerium dioxide (CeO2), cerium nitrate (CeNO3), and manganese dioxide (MnO2).

[0026] In a third aspect, the present invention further provides a proton exchange membrane, including: a reinforcing layer, which is the reinforcing layer for the proton exchange membrane as described above; and a perfluorosulfonic acid layer, which is arranged on one side or both sides of the reinforcing layer, or is arranged alternately with the reinforcing layer.

[0027] Specifically, the present invention includes using electrospinning or 3D printing to perform the structural weaving of the reinforcing layer. The reinforcing layer further includes a dense reinforcing layer and a sparse-dense reinforcing layer, and the reinforcing layer has a catalyst. In some embodiments, due to the low porosity of the dense reinforcing layer, the puncture effect of the anode titanium felt can be effectively prevented. And due to the pore structure of the reinforcing layer and the distribution of the catalyst therein, the proton transport inside the membrane can be effectively improved, the catalyst can be prevented from escaping, and hydrogen permeation can be reduced.

[0028] Furthermore, the present invention proves through some embodiments that the provided proton exchange membrane can solve the aforementioned problems. The proton exchange membrane provided by the present invention has excellent durability, good transport efficiency, and low cost, and is not limited to the above effects. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 It is a structural diagram of the reinforcing layer.

[0030] Figure 2 It is the first flowchart for the preparation of the proton exchange membrane.

[0031] Figure 3 It is the second flowchart for the preparation of the proton exchange membrane.

[0032] Figure 4 It is a polarization curve graph.

[0033] Figure 5 It is a hydrogen permeation result graph. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0034] For the proton exchange membrane 1 described in some embodiments of the present invention, it has a multi-layer structure and has catalytic ability. For example, the proton exchange membrane can be disposed in a proton exchange membrane electrolyzer, and the proton exchange electrolysis membrane cell can be used as a device for implementing proton exchange membrane water electrolysis (PEMWE) technology, but it is not limited.

[0035] In some embodiments of the present invention, the terms "spraying" or "coating" can be achieved through electrospinning technology, or 3D printing technology and its equipment. It can also be understood that in order to form the proton exchange membrane, it is not limited to the above technologies and the same effect may also be achieved.

[0036] In a first aspect, please refer to Figure 1 , in some embodiments of the present invention, a proton exchange membrane 1 is provided, which includes: a reinforcing layer 10, including: a first side 101; and a second side 102, which is disposed relative to the first side 101; wherein the porosity of the reinforcing layer 10 gradually increases from the first side 101 towards the second side 102.

[0037] In some embodiments, the proton exchange membrane 1 further includes a dense reinforcing layer 11, which is disposed on the first side 101, and the porosity of the dense reinforcing layer 11 is less than or equal to the porosity of the first side 101 of the reinforcing layer 10.

[0038] In some embodiments, the proton exchange membrane 1 further includes a sparse-dense reinforcing layer 12, which is disposed on the second side 102, and the porosity of the sparse-dense reinforcing layer 12 is greater than or equal to the porosity of the second side 102 of the reinforcing layer 10.

[0039] Furthermore, one end of the exemplified proton exchange electrolyzer is the anode, and the other end is the cathode. The proton exchange membrane 1 is disposed between the anode and the cathode. Among them, the dense reinforcing layer 11 is close to the anode, and the sparse-dense reinforcing layer 12 is close to the cathode. Herein, when the proton exchange electrolyzer operates, since hydrogen ions (protons) are generated at its anode, the proton exchange membrane 1 only allows the hydrogen ions to pass through and reach the cathode.

[0040] In some embodiments, the porosity of the reinforcing layer 10 is greater than or equal to the porosity of the dense reinforcing layer 11, the porosity of the reinforcing layer 10 is less than or equal to the porosity of the sparse-dense reinforcing layer 12, and the porosity of the reinforcing layer 10 gradually increases in the direction from the dense reinforcing layer 11 to the sparse-dense reinforcing layer 12.

[0041] In some embodiments, the porosity of the dense reinforcing layer 11 is less than the porosity of the sparse-dense reinforcing layer 12.

[0042] Furthermore, in some embodiments, it can be understood that the dense reinforcing layer 11, the reinforcing layer 10, and the sparse-dense reinforcing layer 12 are related to the porosity of the framework formed by the material of the proton exchange membrane 1. That is, the porosity is relatively low in the dense reinforcing layer 11, gradually higher in the reinforcing layer 10, and higher in the sparse-dense reinforcing layer 12. Please refer here Figure 1 , it can be imagined that light colors represent smaller porosities and dark colors represent larger porosities, especially the color of the reinforcing layer 10 shows a gradient.

[0043] In some embodiments, the dense reinforcing layer 11, the reinforcing layer 10, and the sparse-dense reinforcing layer 12 are integrally formed; it can be imagined that by continuous electrospinning and controlling the spraying speed, the dense reinforcing layer 11, the reinforcing layer 10, and the sparse-dense reinforcing layer 12 can be formed in sequence. In other words, the interface effect between layers is eliminated between the dense reinforcing layer 11, the reinforcing layer 10, and the sparse-dense reinforcing layer 12, thereby improving the mechanical strength, electrical conductivity, and durability.

[0044] The spraying speed can be understood as the spraying amount per unit time. In some embodiments, the unit is (mL / h). Simply put, a higher spraying speed can create a higher density, or a higher spraying speed can create a lower porosity. Therefore, controlling the spraying speed can control the porosity.

[0045] In some embodiments, the porosity of the dense reinforcement layer 11 is 10%, 11%, 12%, 13%, 14%, 15%, 16%, 17%, 18%, 19%, 20%, 21%, 22%, 23%, 24%, 25%, 26%, 27%, 28%, 29%, 30%, 31%, 32%, 33%, 34%, 35%, 36%, 37%, 38%, 39%, 40%, 41%, 42%, 43%, 44%, 45%, 46%, 47%, 48%, 49%, 50%, 51%, 52%, 53%, 54%, 55%, 56%, 57%, 58%, 59% or 60%; preferably, the porosity between 30% and 50% is selected.

[0046] In some embodiments, the porosity of the reinforcement layer 10 is a continuously varying range, which is defined by a lowest boundary value and a highest boundary value. Among them, the lowest boundary value is 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50%, 55%, 60%, 65%, 70%, 75% or 80%; the highest boundary value is 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85% or 90%; preferably, the lowest boundary value is selected between 20% and 40%, and the highest boundary value is selected between 50% and 70%.

[0047] In some embodiments, the porosity of the sparse-dense reinforcement layer 12 is 60%, 61%, 62%, 63%, 64%, 65%, 66%, 67%, 68%, 69%, 70%, 71%, 72%, 73%, 74%, 75%, 76%, 77%, 78%, 79%, 80%, 81%, 82%, 83%, 84%, 85%, 86%, 87%, 88%, 89% or 90%; preferably, the porosity between 70% and 90% is selected.

[0048] In some embodiments, the porosity of the reinforcement layer 10, its lowest boundary value is equal to or greater than the porosity of the dense reinforcement layer 11, and the highest boundary value is equal to or less than the porosity of the sparse-dense reinforcement layer 12. Here, it can be understood that the lowest boundary value can specifically refer to the first side 101, and the highest boundary value can specifically refer to the second side 102.

[0049] In some embodiments, the ratio of the porosity of the first side 101 to the porosity of the second side 102 is 1:(1 to 5), preferably 1:(1.2 to 4), more preferably 1:(1.4 to 3). It can be understood that in some embodiments, the ratio of the porosity of the dense reinforcing layer 11 to the porosity of the sparse-dense reinforcing layer 12 is 1:(1 to 5), preferably 1:(1.2 to 4), more preferably 1:(1.4 to 3).

[0050] In some embodiments, the thickness of the dense reinforcing layer 11 is 1 to 20 microns, preferably 2 to 10 microns, more preferably 4 to 8 microns.

[0051] In some embodiments, the thickness of the reinforcing layer 10 is 1 to 20 microns, preferably 2 to 10 microns, more preferably 4 to 8 microns.

[0052] In some embodiments, the thickness of the sparse-dense reinforcing layer 12 is 20 to 90 microns, preferably 40 to 75 microns, more preferably 60 to 80 microns.

[0053] In some embodiments, the total thickness of the dense reinforcing layer 11, the reinforcing layer 10 and the sparse-dense reinforcing layer 12 is 60 to 100 microns, preferably 70 to 90 microns, more preferably 75 to 85 microns.

[0054] In some embodiments, the thickness ratio of the dense reinforcing layer 11 to the reinforcing layer 10 is 1:(0.5 to 5); preferably, the thickness ratio of the dense reinforcing layer 11 to the reinforcing layer 10 is 1:(0.5 to 3); more preferably, the thickness ratio of the dense reinforcing layer 11 to the reinforcing layer 10 is 1:(0.5 to 1.5).

[0055] In some embodiments, the ratio of the total thickness of the dense reinforcing layer 11 and the reinforcing layer 10 to the thickness of the sparse-dense reinforcing layer 12 is 1:(2 to 20); preferably, the ratio of the total thickness of the dense reinforcing layer 11 and the reinforcing layer 10 to the thickness of the sparse-dense reinforcing layer 12 is 1:(4 to 15); more preferably, the ratio of the total thickness of the dense reinforcing layer 11 and the reinforcing layer 10 to the thickness of the sparse-dense reinforcing layer 12 is 1:(5 to 10).

[0056] In some embodiments, the material of the reinforcing layer 10 is selected from one or more of the following: polyphenylene sulfide (PPS), polyethersulfone (PES), polytetrafluoroethylene (PTFE), polyetheretherketone (PEEK), polysulfone (PSU), and polyvinylidene fluoride (PVDF).

[0057] In some embodiments, the material of the reinforcing layer 10 is selected from one or more of the following: sulfonated polyphenylene sulfide (SPPS), sulfonated polyether sulfone (SPES), sulfonated polytetrafluoroethylene (SPTFE), sulfonated polyether ether ketone (SPEEK), sulfonated polysulfone (SPSU), and sulfonated polyvinylidene fluoride (SPVDF).

[0058] In some embodiments, the catalyst 14 includes a metal catalyst, a radical quencher, or any combination thereof; wherein, the metal catalyst includes platinum (Pt), gold (Au), palladium (Pd), or any combination thereof, and the radical quencher includes cerium dioxide (CeO 2 ), cerium nitrate (CeNO 3 ), manganese dioxide (MnO 2 ), or any combination thereof. The catalyst 14 can promote the conversion of hydrogen (H 2 ). In other words, when hydrogen is generated at the anode, passes through the dense reinforcing layer 11, and then passes through the reinforcing layer 10, it will encounter the catalyst 14. At this time, the hydrogen will be eliminated due to the action of the catalyst 14, thereby enabling the proton exchange membrane 1 to have the effect of blocking hydrogen.

[0059] In some embodiments, the mass ratio of the catalyst 14 to the reinforcing layer 10 is 1:(50 to 200), preferably 1:(80 to 180), and more preferably 1:(100 to 150).

[0060] Conceivably, the catalyst 14 is attached to the "skeleton" of the reinforcing layer 10, such as Figure 1 . Similarly conceivably, the catalyst 14 can be "uniformly", "symmetrically", "increasing or decreasingly" distributed in the reinforcing layer 10.

[0061] Furthermore, it can be understood that the catalyst 14 exists in the reinforcing layer 10, and the reinforcing layer 10 is located between the dense reinforcing layer 11 and the sparse-dense reinforcing layer 12. That is to say, on the one hand, the catalyst 14 is attached to the reinforcing layer 10, and on the other hand, it is more protected bidirectionally by the dense reinforcing layer 11 and the sparse-dense reinforcing layer 12. Therefore, it can exist more stably in the reinforcing layer 10. Compared with some poor comparative examples, for example, the catalyst 14 may be formed between the dense reinforcing layer 11 and the reinforcing layer 10, such as only formed on the first side 101 and the second side 102, or it may be a coating by itself; in these examples above, some lose the attachment effect and reduce the bidirectional protection effect between layers, and some will also affect the bonding property between the dense reinforcing layer 11 and the reinforcing layer 10.

[0062] In some embodiments, the reinforcing layer 10, the dense reinforcing layer 11, and the sparse-dense reinforcing layer 12 can be prepared by electrospinning. Among them, the electrospinning voltage is selected between 10 and 25 kV, and the spinning distance is between 5 and 15 cm.

[0063] In some embodiments, the proton exchange membrane 1 further includes: a perfluorosulfonic acid layer disposed on one or both sides of the reinforcing layer 10, or alternately arranged with the reinforcing layer 10.

[0064] In some embodiments, the perfluorosulfonic acid layer further includes a first perfluorosulfonic acid layer formed on one side of the dense reinforcing layer 11 relative to the reinforcing layer 10; and a second perfluorosulfonic acid layer formed on one side of the sparse-dense reinforcing layer 12 relative to the reinforcing layer 10.

[0065] In some scenarios where it is disposed in the proton exchange electrolytic cell, the first perfluorosulfonic acid layer and the second perfluorosulfonic acid layer can be closer to the anode and the cathode than the dense reinforcing layer 11 and the sparse-dense reinforcing layer 12, respectively.

[0066] In some embodiments, the first perfluorosulfonic acid layer and the second perfluorosulfonic acid layer each include a perfluorosulfonic acid resin.

[0067] In some embodiments, the thickness of the first perfluorosulfonic acid layer is 200 to 600 microns, preferably 300 to 500 microns, more preferably 350 to 450 microns; in some embodiments, the thickness of the second perfluorosulfonic acid layer is 200 to 600 microns, preferably 300 to 500 microns, more preferably 350 to 450 microns.

[0068] In some embodiments, the thickness ratio of the first perfluorosulfonic acid layer to the second perfluorosulfonic acid layer is 1:(0.1 to 10), preferably 1:(0.2 to 5), more preferably 1:(0.5 to 1.5).

[0069] Please refer to Figure 2 , Second, the present invention further provides a preparation method P for a reinforcing layer for a proton exchange membrane, including the following steps: P1: Spraying a first dispersion liquid at a gradually changing speed from a first spraying speed to a second spraying speed to form a reinforcing layer 10, wherein the first dispersion liquid has a framework material, and the first spraying speed is greater than the second spraying speed.

[0070] Please refer to Figure 3 , In some embodiments, the preparation method P for the reinforcing layer for a proton exchange membrane further includes the following steps: P2: Spraying the first dispersion liquid at the first spraying speed on one side of the reinforcing layer to form a dense reinforcing layer 11, where P2 precedes P1.

[0071] Please refer toFigure 3 , in some embodiments, the preparation method P of the reinforcing layer for the proton exchange membrane further comprises the following steps: P3: spraying the first dispersion liquid on the side of the reinforcing layer 10 relative to the dense reinforcing layer 11 at the second spraying speed to form a dense and sparse reinforcing layer 12, wherein P3 is subsequent to P1.

[0072] Please refer to Figure 3 , in some embodiments, the preparation method P of the reinforcing layer for the proton exchange membrane further comprises the following steps: P4: simultaneously or alternately with P1, spraying a second dispersion liquid at a third spraying speed to jointly form the reinforcing layer 10, wherein the second dispersion liquid has a catalyst.

[0073] In some embodiments, the preparation method P of the reinforcing layer for the proton exchange membrane further comprises: P5: drying the dense reinforcing layer 11, the reinforcing layer 10 and the dense and sparse reinforcing layer 12.

[0074] In some embodiments, the framework material includes polyphenylene sulfide (PPS), polyethersulfone (PES), polytetrafluoroethylene (PTFE), polyetheretherketone (PEEK), polysulfone (PSU), polyvinylidene fluoride (PVDF) or any combination of the above.

[0075] In some embodiments, the framework material includes sulfonated polyphenylene sulfide (SPPS), sulfonated polyethersulfone (SPES), sulfonated polytetrafluoroethylene (SPTFE), sulfonated polyetheretherketone (SPEEK), sulfonated polysulfone (SPSU), sulfonated polyvinylidene fluoride (SPVDF) or any combination of the above.

[0076] In some embodiments, the catalyst includes a metal catalyst, a radical quencher or any combination of the above, wherein the metal catalyst includes platinum (Pt), gold (Au), palladium (Pd) or any combination of the above, and the radical quencher includes cerium dioxide (CeO 2 ), cerium nitrate (CeNO 3 ), manganese dioxide (MnO 2 ) or any combination of the above.

[0077] In some embodiments, the first spraying speed is greater than or equal to the second spraying speed.

[0078] In some embodiments, the second spraying speed is greater than or equal to the third spraying speed.

[0079] In some embodiments, the ratio of the first spraying speed to the second spraying speed is 1:(0.1 to 1), preferably 1:(0.1 to 0.8), more preferably 1:(0.1 to 0.5).

[0080] In some embodiments, the ratio of the first spraying speed, the second spraying speed and the third spraying speed is 1:(0.1 to 1):(0.1 to 1), preferably 1:(0.1 to 0.8):(0.1 to 0.8), and more preferably 1:(0.1 to 0.5):(0.1 to 0.5).

[0081] In some embodiments, the first spraying speed is 0.01 to 0.5 mL / h, preferably 0.01 to 0.2 mL / h, and more preferably 0.01 to 0.1 mL / h.

[0082] In some embodiments, the second spraying speed is 0.01 to 0.5 mL / h, preferably 0.01 to 0.2 mL / h, and more preferably 0.01 to 0.1 mL / h.

[0083] In some embodiments, the third spraying speed is 0.01 to 0.2 mL / h, preferably between 0.02 and 0.05 mL / h.

[0084] It can be further understood that in some embodiments, the material of the reinforcing layer 10 is dissolved in the first solvent to form the first dispersion. Among them, the first solvent includes dimethylacetamide (DMAC), dimethylformamide (DMF), dimethyl sulfoxide (DMSO) or any combination of the above. Thus, after spraying or coating the first dispersion, the first solvent can be removed through a drying step, and then the structures of the dense reinforcing layer 11, the reinforcing layer 10 and the dense-sparse reinforcing layer 12 are formed.

[0085] In some embodiments, the concentration of the material of the reinforcing layer 10 in the first dispersion is 5% to 30%; preferably 10% to 30%; more preferably 15% to 25%.

[0086] It can be further understood that in some embodiments, the catalyst 14 is dissolved in the second solvent to form the second dispersion. Among them, the second solvent includes water, ethanol, propanol, isopropanol or any combination of the above. Thus, after spraying or coating the second dispersion, the second solvent can be removed through a drying step, and then the catalyst 14 is retained or generated.

[0087] In some other embodiments, the catalyst 14 is a nanomaterial. In other words, the metal catalyst includes platinum (Pt), gold (Au), palladium (Pd), or the radical quencher includes cerium dioxide (CeO 2 )、cerium nitrate (CeNO 3 )、manganese dioxide (MnO 2 ) can be nanoparticles.

[0088] In some embodiments, the concentration of the catalyst 14 in the second dispersion is 0.1% to 10%, preferably 0.2% to 5%, and more preferably 0.5% to 2%.

[0089] In some embodiments, before the catalyst 14 is dissolved in the second solvent, it can be optionally mixed with a perfluorosulfonic acid dispersion (such as Nafion TM dispersion) in a ratio of 1:(2 to 20), wherein preferably the catalyst 14 and the perfluorosulfonic acid dispersion are mixed in a ratio of 1:(1 to 10), and more preferably in a ratio of 1:5.

[0090] In some aspects, the present invention further provides a method N for preparing a proton exchange membrane, including: N1: obtaining a reinforcing layer for a proton exchange membrane, which is prepared by the preparation method P of the reinforcing layer for the proton exchange membrane; and N2: spraying a third dispersion on the surface or any side of the reinforcing layer for the proton exchange membrane at a fourth spraying speed to form a perfluorosulfonic acid layer.

[0091] It can be understood that the perfluorosulfonic acid resin (PFSA) is dissolved as a solute in a third solvent to form the third dispersion, wherein the third solvent includes water, ethanol, propanol, isopropanol or any combination thereof; thus, after the third dispersion is sprayed or coated, the third solvent can be removed by a drying step, and then the perfluorosulfonic acid layer is produced.

[0092] That is to say, in some embodiments, the method N for preparing the proton exchange membrane further includes: N3: drying the perfluorosulfonic acid layer to form the proton exchange membrane.

[0093] It can also be understood that when performing N2, the third dispersion will fill the pores of the reinforcing layer for the proton exchange membrane, resulting in a composite situation.

[0094] In some embodiments, the third solvent is a mixture of ethanol and deionized water in a ratio of (1 to 10):1, and the ratio is preferably (1 to 5):1, and more preferably (2 to 4):1.

[0095] In some embodiments, the ion exchange equivalent (EW value) of the third dispersion is between 700 and 1100 (grams / mole, g / mol).

[0096] In some embodiments, the solid content of the third dispersion is 10% to 30%.

[0097] In some aspects, the present invention provides a hydrogen production device, which includes the proton exchange membrane 1 as described above. It can be understood that the hydrogen production device includes a proton exchange membrane electrolyzer (PEM electrolyzer), which is selectively connected to a proton exchange membrane fuel cell (Proton Exchange Membrane Fuel Cell, PEMFC) and supplies hydrogen to the proton exchange membrane fuel cell.

[0098] The following specific examples further illustrate the essential features of the present invention.

[0099] Example 1

[0100] Material preparation:

[0101] (1) Electrospinning solution: The sulfonated polyether ether ketone (PEEK) powder is used as a solute and dissolved in a dimethylformamide (DMF) solvent to form an electrospinning solution with a solid content of 20 wt%.

[0102] (2) Catalyst: A solution of platinum (pt) and Nafion TM ) with a concentration of 1%, where platinum is used as a catalyst and the weight ratio of platinum to Nafion is 1:0.25.

[0103] (3) Perfluorosulfonic acid dispersion: Weigh 2 grams of perfluorosulfonic acid (PFSA) resin, add it to a mixed solvent of 24 grams of ethanol and 8 grams of deionized water, and then place the mixed solution in an autoclave. React at a temperature of 230 °C and a rotation speed of 500 r·min -1 for 6 to 8 hours under the conditions for dissolution to obtain a perfluorosulfonic acid dispersion.

[0104] Implementation steps:

[0105] (S1) Form a dense reinforcing layer: Use an electrospinning machine and take an electrode plate. The voltage is set to 20 KV, the distance from the tip of the spraying needle to the electrode plate is set to 10 cm, and the spraying speed is set to 0.05 ml / h. Thus, spray the electrospinning solution to form a dense reinforcing layer with a first thickness.

[0106] (S2) Form a reinforcing layer: Continuously, control the spraying speed to gradually change from 0.05 ml / h to 0.02 ml / h, spray the electrospinning solution to form a reinforcing layer with a second thickness. At the same time, spray the catalyst at a spraying speed of 0.03 ml / h so that the catalyst is distributed in the reinforcing layer.

[0107] (S3) Form a dense and sparse reinforcing layer: Continuously, spray the electrospinning solution at a spraying speed of 0.02 ml / h until the total thickness reaches 80 micrometers (μm) to form a dense and sparse reinforcing layer.

[0108] (S4): Place the products of the above (S1) to (S3) in an oven and bake at 130 °C for 2 hours to remove the residual solvent and complete the heat setting. Thus, a dense reinforcing layer, a reinforcing layer, and a sparse-dense reinforcing layer with a three-layer structure are obtained.

[0109] (S5): Double-sidedly coat the perfluorosulfonic acid dispersion on the reinforcing layer: Take a release film and scrape and coat a resin solution with a thickness of 400 microns. Then, place the dense reinforcing layer, the reinforcing layer, and the sparse-dense reinforcing layer with the three-layer structure with its sparse-dense reinforcing layer close to and attached to the release film; after drying, coat a layer of perfluorosulfonic acid dispersion with a thickness of 400 microns on the dense reinforcing layer and wait for drying again.

[0110] (S6): Place the dense reinforcing layer, the reinforcing layer, and the sparse-dense reinforcing layer with the three-layer structure in an oven and bake at 80 °C for 30 minutes to remove the residual solvent. Then, bake at 140 °C for 1 hour to complete the thermal curing and obtain the sample to be tested.

[0111] Testing method:

[0112] The conductivity test is carried out according to the conductivity test standard in GB / T 20042.3-2022, and the anti-puncture pressure is tested according to the requirements of 6.5.3.2 in GB / T 36363-2018.

[0113] Example 2: The difference from Example 1 is that in the catalyst, the catalyst platinum (Pt) in Example 1 is replaced by cerium oxide (CeO 2 ).

[0114] Example 3: The difference from Example 1 is that in (S2), the second thickness changes.

[0115] Example 4: The difference from Example 1 is that in the electrospinning solution, sulfonated polyether ether ketone (PEEK) is replaced by polyvinylidene fluoride (PVDF).

[0116] Example 5: The difference from Example 1 is that (S1) is not included, that is, the preparation of the dense reinforcing layer is not carried out, and the total thickness in (S3) is still controlled to be 80 microns.

[0117] Comparative Example 1: The difference from Example 1 is that the spraying of the electrospinning solution in (S2) is not included, but the spraying of the catalyst is still retained, and the total thickness in (S3) is still controlled to be 80 microns.

[0118] Comparative Example 2: The difference from Example 1 is that (S1) is not included, that is, the preparation of the dense reinforcing layer is not carried out, and the spraying of the catalyst in (S2) is not carried out either, and the total thickness in (S3) is still controlled to be 80 microns.

[0119] Comparative Example 3: The difference from Example 1 is that it does not include (S1) nor (S2), that is, the preparation of the dense reinforcing layer and the reinforcing layer is not carried out, and the total thickness in (S3) is still controlled to be 80 microns.

[0120] Comparative Example 4: The difference from Example 1 is that in (S2), the spraying speed of the electrospinning solution gradually changes from 0.02 ml / h to 0.05 ml / h to form a reinforcing layer with a second thickness, and the total thickness in (S3) is still controlled to be 80 microns.

[0121] Comparative Example 5: The difference from Example 1 is that in (S2), the spraying speed of the electrospinning solution gradually changes from 0.05 ml / h to 0.02 ml / h. After waiting for the electrospinning solution to be completed, the catalyst is sprayed at a speed of 0.03 ml / h, and the total thickness in (S3) is still controlled to be 80 microns.

[0122] The test data of each example and comparative example are presented in Table 1, where the synergy multiplier (conductivity × puncture resistance) is used to comprehensively evaluate the performance of each example and comparative example.

[0123] Table 1

[0124] As recorded in Table 1:

[0125] (1) According to the synergy multiplier, it can be found that Examples 1 to 5 have a score of more than 3.75, all higher than each comparative example.

[0126] (2) Observing Example 1, Comparative Example 2 and Comparative Example 3, the puncture resistance of Comparative Example 2 and Comparative Example 3 is lower in the case of lacking the dense reinforcing layer (the first thickness is 0); that is to say, the presence of the dense reinforcing layer can improve the overall puncture resistance.

[0127] (3) Sequentially observing Example 3, Example 1 and Comparative Example 1, when the second thickness decreases from 8 microns, 5 microns to 0 microns, their conductivities also decrease from 0.15, 0.14 to 0.11 respectively; that is to say, the presence of the reinforcing layer can provide the effect of improving conductivity.

[0128] (4) Comparing Example 1 and Comparative Example 4, the gradient of the electrospinning solution in Example 1 in terms of spraying speed is gradually decreasing, which causes the porosity of the reinforcing layer to gradually increase towards the dense and sparse reinforcing layer. On the other hand, the gradient of the electrospinning solution in Comparative Example 4 in terms of spraying speed is gradually increasing, which causes the porosity of the reinforcing layer to gradually decrease towards the dense and sparse reinforcing layer; in comparison, the conductivity and anti-puncture pressure performance of Example 1 are both better, while the conductivity and anti-puncture pressure performance of Comparative Example 4 are both worse.

[0129] (5) Comparing Example 1 and Comparative Example 5, the catalyst in Example 1 is distributed in the reinforcing layer, while the catalyst in Comparative Example 5 is between the reinforcing layer and the dense and sparse reinforcing layer. Obviously, the conductivity provided by Example 1 is better.

[0130] As Figure 5 presented:

[0131] Compared with Comparative Example 1, Comparative Example 2, and Comparative Example 3, the hydrogen permeation amounts of Example 1 and Example 5 are the lowest and the second lowest.

[0132] The above are only several preferred embodiments of the present invention, but the patent protection scope of the present invention cannot be limited thereby; therefore, all simple equivalent changes and modifications made according to the patent protection scope and the content of the specification of the present invention shall fall within the patent protection scope of the present invention.

Claims

1. A reinforcement layer for a proton exchange membrane, characterized in that: include: First side; as well as a second side disposed relative to the first side; in The porosity of the reinforcement layer increases gradually from the first side toward the second side.

2. The proton exchange membrane reinforcement layer according to claim 1, characterized in that: It also includes a dense reinforcement layer, which is arranged on the first side, and the porosity of the dense reinforcement layer is less than or equal to the porosity of the first side.

3. The proton exchange membrane reinforcement layer according to claim 2, characterized in that: It also includes a density enhancement layer, which is arranged on the second side, and the porosity of the density enhancement layer is greater than or equal to the porosity of the second side.

4. The proton exchange membrane reinforcement layer according to claim 1, characterized in that: A ratio of the porosity of the first side to the porosity of the second side is 1:(1 to 5).

5. The proton exchange membrane reinforcement layer according to claim 3, characterized in that: The thickness ratio of the dense reinforcement layer to the reinforcement layer is 1:(0.5 to 5), and the thickness ratio of the sum of the dense reinforcement layer and the reinforcement layer to the thickness of the sparse reinforcement layer is 1:(2 to 20).

6. The proton exchange membrane reinforcement layer according to claim 1, characterized in that: The material is selected from one or more of the following: polyphenylene sulfide (PPS), polyethersulfone (PES), polytetrafluoroethylene (PTFE), polyetheretherketone (PEEK), polysulfone (PSU), polyvinylidene fluoride (PVDF), and sulfonates of any of the above materials.

7. The proton exchange membrane reinforcement layer according to claim 1, characterized in that: Contains a catalyst.

8. The proton exchange membrane reinforcement layer according to claim 7, characterized in that: The catalyst includes a metal catalyst, a free radical quencher or any combination thereof.

9. The proton exchange membrane reinforcement layer according to claim 8, characterized in that: The metal catalyst is selected from one or more of the following: platinum (Pt), gold (Au) and palladium (Pd).

10. The proton exchange membrane reinforcement layer according to claim 8, characterized in that: The free radical quencher is selected from one or more of the following: cerium dioxide (CeO2), cerium nitrate (CeNO3) and manganese dioxide (MnO2).

11. The proton exchange membrane reinforcement layer according to claim 7, characterized in that: The mass ratio of the catalyst to the reinforcement layer is 1:(50 to 200).

12. The proton exchange membrane reinforcement layer according to claim 1, characterized in that: It is prepared by electrospinning.

13. A method for preparing a reinforcement layer for a proton exchange membrane, characterized in that: The following steps are involved: P1: spraying a first dispersion at a first spraying speed gradually changing to a second spraying speed to form a reinforcement layer, wherein the first dispersion has a skeleton material, and the first spraying speed is greater than the second spraying speed.

14. The preparation method according to claim 13, characterized in that: The following steps are also included: P2: spraying the first dispersion on one side of the reinforcement layer at the first spraying speed to form a dense reinforcement layer, wherein the P2 is disposed before the P1.

15. The preparation method according to claim 14, characterized in that: The following steps are also included: P3: spraying the first dispersion at the second spraying speed on the side of the reinforcement layer opposite to the dense reinforcement layer to form a dense reinforcement layer, wherein the P3 is arranged on the After P1.

16. The preparation method according to claim 15, characterized in that: The following steps are also included: P4: simultaneously or alternately with P1, spraying a second dispersion at a third spraying speed to form the reinforcement layer together with the first dispersion, wherein the second dispersion contains a catalyst.

17. The preparation method according to claim 16, characterized in that: The ratio of the first spraying speed, the second spraying speed and the third spraying speed is 1:(0.1 to 1):(0.1 to 1).

18. The preparation method according to claim 13, characterized in that: The skeleton material is selected from one or more of the following: polyphenylene sulfide (PPS), polyethersulfone (PES), polytetrafluoroethylene (PTFE), polyetheretherketone (PEEK), polysulfone (PSU), polyvinylidene fluoride (PVDF) and sulfonates of any of the above materials.

19. The preparation method according to claim 15, characterized in that: The catalyst includes a metal catalyst, a free radical quencher or any combination thereof, wherein the metal catalyst is selected from one or more of the following: platinum (Pt), gold (Au) and palladium (Pd), and the free radical quencher is selected from one or more of the following: cerium dioxide (CeO2), cerium nitrate (CeNO3) and manganese dioxide (MnO2).

20. A proton exchange membrane, characterized in that: include: A reinforcement layer, a reinforcement layer for a proton exchange membrane according to any one of claims 1 to 12; as well as The perfluorosulfonic acid layer is arranged on one side or both sides of the reinforcing layer, or is arranged alternately with the reinforcing layer.

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